Progressive cavity pump

摘要

Eccentric screw pump with an outer annular part and an inner part where the outer part interior and the inner part exterior are tapered towards an axial end. The inner and outer parts can move relative to each other in the axial direction (X,W). The surface of the inner part can consist of ceramic while the part of the outer part opposite to the inner part surface can consist of elastomer. The inner and/or outer parts are configured so that the pressure applied to the pressure side of the eccentric screw pump generates a force which acts on the inner part axially to the taper direction of the inner part and/or a force acts on the outer part in the opposite axial direction.